First off Edzer, thanks for developing the library. It greatly enhances R's 
spatial capabilities.

This question is perhaps more an R question than a Gstat one, but it relates, 
so I'll ask anyway. I wish to display interpolated surfaces (kriging 
predictions and variances), but I also wish to overlay the sample points. the 
image function works ok for visualizing the surface, and points(x,y) overlays 
the samples on the points. However, Image lacks a legend bar.

The R alternative appears to be the levelplot command. Levelplot makes a nice 
surface with a legend. However, points does not work with lattice, and 
lpoints (as suggested in the gstat R documentation and in the lattice 
writeups) does not produce output. A code snippet follows:
> levelplot(sqrt(var1.var) ~ x + y, ni.sk, aspect=mapasp(ni.sk), 
+ main="Ni SK Standard Errors") 
> lpoints(jura$x,jura$y)

The first line produces the expected map without problems. The second line 
gives no warnings or errors but also fails to draw any points on the image. 
Various settings of pch, col, etc. (parameters to the points command) were 
unsuccessful.

I've reproduced this problem on Windows and Linux versions of R 1.62.

Anyone know what the problem might be?

Thanks very much in advance,

Ashton 

-- 
Ashton Shortridge               [EMAIL PROTECTED]
Assistant Professor             http://www.msu.edu/~ashton
Dept. of Geography              (517) 432 - 3561
Michigan State University               

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